Replaced head gasket, new injectors... Not starting

[berksbr]

I have a 93 CTD W250 with 220k miles and recently had the head completely redone, replaced the head gasket, and purchased Bosch 190 injectors. Put it all back together and engine is not starting. This is by far my biggest project. I am not a mechanic but have done the rear brakes, injection pump, and a new clutch with help from friends...

The truck was apart for six months and I did reuse the head bolts. I know I need air, fuel, and compression for it to start, but how do I isolate these specifics, at this point, to figure out what is causing the engine not to turn over???

Any suggestions or reccomendations would be greatly appreciated... Need to get the old girl running again, been missing her...

Thanks in Advance,

 

[STeichert]

Is the engine not turning over, or does it crank and not start? If it is cranking you may not be getting fuel to the injectors because of a lot of air in the lines. I have had some that were hard to bleed and have had to pressurize the fuel tank by blowing air in the fuel fill tube with a rag wrapped around my air chuck. Be sure to use low pressure when doing this.

 

[HHhuntitall]

Have you bled injector lines?

 

[berksbr]

It cranks but does not start. I thought i bled my injector lines enough but maybe not... When I did the injection pump last year and bled the lines I seem to remember more fuel coming out of the injection lines. This time it seemed week and took quite a bit of time to get fuel to come out.

What about the fuel heater? I purchased a new gasket for it. Should I just delete it?

So do you actually blow air into where you fill up the gas? If you could elaborate a little more and I will try that.

 

[HHhuntitall]

First, I would verify the lift pump is working, pumping fuel to the fuel filter. There should be a vent nut on top of the fuel line where it comes out of the head directly above the fuel filter... . this will vent air from the filter until it's full, then it will purge diesel. Then I'd suggest loosening the return line on the pump until it starts to leak diesel, priming by hand at the fuel lift pump priming lever. It can take a long time if it's drained the filter and pump. The pump has to be full before it'll start priming the lines and injectors... ...



Also, make sure you have electricity at the fuel shut off solenoid, on the back of the pump, in front of the injector lines..... There is a possibility this can stick over time, but it's not real common. It is common for it to lose power or have a bad connection from the key... ...



Air pressure in the fuel tank can help in priming the pump, but it won't solve the problem if the lift pump is faulty. I don't recommend it, and it can cause other issues, even with small amounts of pressure.



Oh, and on the grid heaters, that's a personal decision. IF it's cold in the winter and you start it regular without being plugged in, they help with starting. I keep them on, just in case it gets real cold here, as long as they work. But it seldom stays below freezing more than a few days at a time. I had a 91 at one point I unplugged, as the PCM kept cycling them, even when it was 70+* outside. It starts fine in cold weather, though, and it was 7* that winter they quit. I deleted the ones on my '03, but that was for performance reasons..... The great boys at Wilson and TDR let me have a Wilson Thrasher intake manifold for smart-alec remarks about why we deserved one..... Actually won something with my wit!!

 

[STeichert]

I have had the fuel heater suck air on several engines, but the only 1st gen engine that did it was the bolt that holds it on had come loose (between the fuel filter and heater). You need to remove the filter and then underneath in the center of the heater is allen nut you can remove or tighten. I left the one on the 1st gen, but have removed all of the 2nd gen ones I have worked on because they do cause problems. That could be something to try. As for the air pressure, I had an engine that would not prime for anything, so yes I did pressurize it where you fuel up. As stated above it can cause problems, so it's not the best thing to do. That truck ended up having a bad lift pump, and since changing that I have had no more priming problems after a fuel filter change. The 1st gen lift pumps do go out, I have changed many over the years and they are not to expensive. Sometimes you have to bump the starter to get the cam lobe to turn to the right position so the little hand lever will work. If the lever feels like it pushes to easy, or it is not grabbing fuel that could be why it is not pumping fuel. I am thinking this is a fuel issue and you are on the right track.

 

[DVolk]

hook a small bottel of fuel directly bto the pump and see if it will fire that way maybe your lift pump is bad ?

 

[berksbr]

I put a new lift pump on when i did the injection pump last year and everything was good.

The allen screw your refering to has two sets of threads, correct? One that screws into to hold the fuel heater to the head, and the other set of threads to hold the fuel filter on. Just making sure I'm not missing something here...

I will double check that everything is snug, tight, and gaskets are in place with fuel heater. Will also double check that the plastic housing on the fuel heater is not cracked. This is the one thing i did'nt take off before i had the head redone and when i got it back i was like what is this and where does it go...

Once everything is confirmed i will bleed my lines as recommended. Keep you posted.


Thanks Again

 

[DVolk]

the fuel heater is just above the fuel filter i hear people illimanateing them how is it done ?

 

[HHhuntitall]

There is a center, screwed in, adapter that goes up into the block to hold the heater on. If you pull that thread, it's internally a 6 point allen, pull it out, it looks like a close pipe coupler, then you can screw it all the way back up into the head, and then screw the filter directly to the head, instead of to the heater assembly. Both use the same square O-ring on top to seal off.

 

[DVolk]

I might have to check that out or just get one to replace it , mine i think could be leaking off after the truck sits over night

 

[DVolk]

I might have to check that out or just get one to replace it , mine i think could be leaking off after the truck sits over night

 

[HHhuntitall]

I might have to check that out or just get one to replace it , mine i think could be leaking off after the truck sits over night

I've seen a lot of them in the last few years that just need a new gasket over the fuel heater, between it and the head... ... If that gets a crack, or just gets stiff, it can leak some. Pull it out, and see if it uses the same gasket as the filter. I think it does, and the next time you pull the filter, pull the old gasket off that filter, and put it on the fuel heater... ..... I can't remember if that fixes it or if I had to go to Cummins for the gasket..... CRS diesease... Getting old sucks, don't ever do it!! :-laf

 

[DVolk]

ill check that out , i hear ya i get brain farts as well

 

[berksbr]

Update:

Today I cranked the truck over with one injector open with the fuel shut off solenoid hooked up and once without... Realized there was no change in the amount of fuel coming out of the injector and confirmed what I thought was weak fuel pressure at the injector. Connected a wire from the solenoid directly to the battery and heard the ball moving, so I knew it was working. Temporarily rigged it up to the battery and it cranked right over!

Now I gotta figure out why there is no power getting to solenoid. Fun, Fun. Going to look for previous posts on this issue to help trouble shoot.

Thanks again,

 

[HHhuntitall]

Are the guages, lights, and other things all working in the cab?

 

[DVolk]

could you get it to fire with the jumper hooked to the battery ? id say a bad fusible link

 

[berksbr]

Gauges are working, dome lights don't work because I think it's burned out.

Yes I hooked the jumper straight to the battery. Where is the fuseible link located?

The other end of the fuel shut off solenoid wire just plugs into the top of the air intake, correct? Really wasn't clear on how it was drawing power from the battery or does the power going to the grid heater also power the fuel shut off solenoid???

 

[HHhuntitall]

Gauges are working, dome lights don't work because I think it's burned out.



Yes I hooked the jumper straight to the battery. Where is the fuseible link located?



The other end of the fuel shut off solenoid wire just plugs into the top of the air intake, correct? Really wasn't clear on how it was drawing power from the battery or does the power going to the grid heater also power the fuel shut off solenoid???

Fusible links are mostly on the driver fender, above the grid heater relays. They come directly off the battery to a triangular, rubber, divider that breaks off into, I believe, four seperate fusible links going into the wireloom. I'll try to get a pic tomorrow if I can remember.



The power feed for the fuel shutoff soleniod is fed from the keyed accessories. When you turn the key on, it provides power. The wire runs up and connects at one of two connectors near the back of the engine on the driver side. That, in turn, connects to the main wire loom. I'm not sure what circuit feeds it, but I'll try to look at that tomorrow, too. I'm presuming you've checked all your fuses in the panel?

 

[DVolk]

You still never answerd the question if you run a hot jumper from the battery to the fuel shut off relay will it fire and run ?you need to do this before messing with the wireing this will weed out lots of issues to start looking at .